Psychonotis caelius plateni ( Grose-Smith & Kirby, 1896 )

Schröder, Stefan, 2019, Notes on the genus Psychonotis (Lepidoptera: Lycaenidae) from Western New Guinea (Papua and Papua Barat), with description of a new subspecies of P. melane (Joicey & Talbot, 1916), Sugapa Digital 11 (2), pp. 79-86 : 81-82

Psychonotis caelius plateni ( Grose-Smith & Kirby, 1896)

( Figs 1-16 )

Thysonotis plateni Grose-Smith & Kirby, 1896: 40 , pl. 3 fig. 5-6.

Thysonotis plotinus Grose-Smith & Kirby, 1896: 44 , pl. 4 fig. 5-7. syn. nov.

Grose-Smith & Kirby described plateni from material collected by Platen on his expeditions to Waigeo during the 1880s. Psychonotis caelius plateni closely resembles ssp. plotinus , which was described a few pages later in the same publication and the given illustrations of both species serve very well to understand their proposed separation.

Psychonotis caelius plateni and plotinus are of about the same size and have a similar underside wing pattern. The main differences, as seen from the original drawings, are the narrower band of marginal ocelli and the white marginal striae in plateni . Accordingly, the white hindwing band is slightly broader in plateni than in plotinus .

Longer series of plateni from Western New Guinea, including some offshore islands, show that there is a wide range of variation in both males and females. In the males, the width of the discal bands on both fore- and hindwing varies; they may be reduced in width towards the inner margin of the hindwing or end as a broad band. Accordingly, the width of the dark median band also varies. The marginal lunules are also variable. Usually they are well developed but in some populations like in specimens occurring in the Arfak Mountains ( P. caelius cf. plateni , Fig. 17-18 ) they are reduced in width. Females are also very variable. The white discal bands vary in width but are generally much narrower than in the males and usually there is some metallic blue basal scaling on the upperside ( Fig. 7-12 ).

The white marginal streaks on the hindwing are present in almost all males and females, even though they may be only faintly developed. In some localities, like Timika ( Fig. 10 ), rare specimens with greatly reduced streaks occur ( Fig. 10a ), which otherwise do not differ from phenotypes of other populations.

Two males from the Dau River determined as P. caelius cf. plateni (Peg. Bintang Batimban, KSP 12090; 12091, Fig. 21-22 ) have the dark hindwing margin broadened and the green metallic marginal lunules strongly reduced, but in all other characters they do not differ from plateni , and especially females show no difference at all. Marginal white streaks are faintly developed. Most likely they belong to montane population, as broadened hindwing margins are also, but to a lesser extent, present in specimens from the Arfak Mountains. However, there appears to be no general trend that may be useful to separate different geographical races.

As the characters of the underside pattern vary, the main difference between both subspecies appears to be the “row of narrow white streaks” (Grose- Smith & Kirby, 1896: 40) at the hindwing margin in plateni . Grünberg in Seitz (1928: 829) refers to these marginal hindwing markings as an “unterbrochene weisse Saumlinie” and D’Abrera (1977: 328), described it as “a small row of white marginal spots” on the hindwing, which are lacking in plotinus . In their original diagnosis of T. plotinus, Grose-Smith & Kirby (1896: 44) are describing a “submarginal row of oval black spots, separated from the rest of the black border by the metallic blue surrounding them” and there is no indication of a white marginal line in the figures given on their plate ( Grose-Smith & Kirby, 1896: pl. 4, fig. 6). However, marginal white streaks are very obvious in their figure given for plateni ( Grose-Smith & Kirby, 1896: pl. 3 fig. 6).

Considering the very slight differences between plateni and plotinus both are here considered synonyms, with plateni having page priority over plotinus .

Distribution: Fruhstorfer (1915: 42) had already recognized that: “Eine ähnliche Form kommt in Sorong, Holl. Nord-west-Neu-Guinea vor. Nach Druce finden sich benachbarte Stücke auch auf Mysole und Dorey“[A similar form occurs at Sorong, Holl. Nord-west-Neu- Guinea. According to Druce, related specimens can also be found on Mysole and Dorey]. Fruhstorfer’ s observation can be confirmed and apparently, plateni is distributed throughout Western New Guinea (Kaimana, Sorong, Japen, FakFak, Avona, Timika, Arfak, Nabire). Specimens occuring at Bulolo ( PNG) do not differ much and it appears that the range of plateni includes much of mainland New Guinea.

Remarks concerning the taxon plotinus Grose-Smith & Kirby, 1896 :

Thysonotis plotinus was originally described from “Stephansort” (now Bogadjim) at the northern coast in the Madang Province of Papua New Guinea and Parsons (1998) has included all PNG mainland populations in ssp. plotinus , while D`Abrera (1977: 328) imprecisely restricted the distribution of plotinus to Eastern New Guinea and questionably New Britain.

Parsons (1998: pl. 68, figs. 1913, 1915) illustrates a male and a female as ssp. plotinus from PNG, both with well developed white marginal streaks, which are not characteristic for this subspecies but for plateni . Müller (2003: fig. 10) also figured a similar male specimen from the Central Highlands of PNG with well developed marginal streaks. Specimens from the Madang Province (Tokan) and Morobe Province (Bulolo), which is situated about 400 km south of Stephansort, also possess the white marginal line and do not differ significantly from specimens from West Papua ( Fig. 16a ).

The variation observed in P. caelius plateni is very wide and it appears that this also includes phenotypes previously known as “ plotinus ”. A separation of both forms, based on the width of the white discal bands or the metallic submarginal lunules is impossible. As already discussed above, plotinus is considered to be a synonym of plateni and can therefore only be regarded as a variation of plateni .

Figures

Figs 1-16. Psychonotis caelius plateni (Grose-Smith & Kirby, 1896) [all in CSSK]. Fig. 1. ♂, upperside, Waigeo, no date; Fig. 2. underside; Fig. 2a. Hindwing showing the green metallic lunules and white marginal streaks; Fig. 3. ♂, upperside, Waigeo, x.2009; Fig. 4. underside; Fig. 5. ♂, upperside, Nabire, Kaladiri vill., xii.2013; Fig. 6. underside; Fig. 7. ♀, upperside, Sorong, i.2012; Fig. 8. underside; Fig. 9. ♀, upperside, Timika, vi.2001; Fig. 10. underside; Fig. 10a. Hindwing with reduced marginal streaks; Fig. 11. ♀, upperside, Yapen, Ambaidiru, iii.2006; Fig. 12. underside; Fig. 13. ♂, upperside, Bulolo, vi.2001; Fig. 14. underside; Fig. 15. ♂, upperside, Madang, Tokan vill., vi.2001; Fig. 16a. Hindwing with well developed marginal streaks. [scale for set specimens = 1cm]

Figs 17-22. Psychonotis caelius cf. plateni (Grose-Smith & Kirby, 1896). Fig. 17. ♂, upperside, Arfak Mountains., ix.2013, CSSK; Fig. 18. underside; Fig. 19. ♀, upperside, Arfak Mountains., Duebei, 1200m, i.2011, CSSK; Fig. 20. underside; Fig. 21. ♂, upperside, Peg. Bintang, Batimban, Dau River, vii.2003, KSP12091; Fig. 22. Underside; Fig. 23. Psychonotis caelius dissimilis (Joicey & Talbot, 1916), ♂ upperside, Supiori Isl., viii.-ix.2006, CSSK; Fig. 24. underside; Fig. 25. Psychonotis eudocia Druce & Bethune-Baker, 1893, ♂, upperside, Bacan, Labuha, ix.2015, CSSK; Fig. 26. Underside (note the short yellowish streak at the forewing base); Fig. 27. Psychonotis melane melane (Joicey & Talbot, 1916), ♂, upperside, Wissel Lake, Tuguwai, xii.1980, KSP11926; Fig. 28. underside; Fig. 29. Psychonotis melane astra subsp. nov., ♂, paratype, upperside, Star Mountains, Peg. Bintang, Mabilabol, ii.2005, KSP 11928; Fig. 30. underside; Fig. 31. Psychonotis melane astra subsp. nov., ♂, holotype, upperside, Star Mountains, Peg. Bintang, Mabilabol, ii.2005, KSP11930; Fig. 32. underside; Fig. 33. Psychonotis melane melane (Joicey & Talbot, 1916), ♂, left valva, KSP11924. Fig. 34. Psychonotis melane astra subsp. nov., ♂, left valva (note the more rectangular outline and the slightly stronger teeth), KSP11928. [scale for set specimens = 1cm]